Cleanups and minor refactors.

Co-authored-by: Jack Grigg <jack@electriccoin.co>

src/circuit/gadget/sinsemilla.rs

@@ -139,8 +139,8 @@ where
         Self {
             chip,
             inner: pieces
-                .iter()
-                .map(|piece| piece.inner.clone())
+                .into_iter()
+                .map(|piece| piece.inner)
                 .collect::<Vec<_>>()
                 .into(),
         }
@@ -354,13 +354,11 @@ mod tests {
                 meta.fixed_column(),
                 meta.fixed_column(),
             ];
-            let constants_3 = meta.fixed_column();
 
             let perm = meta.permutation(
                 &advices
                     .iter()
                     .map(|advice| (*advice).into())
-                    .chain(Some(constants_3.into()))
                     .chain(constants_1.iter().map(|fixed| (*fixed).into()))
                     .chain(constants_2.iter().map(|fixed| (*fixed).into()))
                     .collect::<Vec<_>>(),

src/circuit/gadget/sinsemilla/chip.rs

@@ -72,12 +72,6 @@ pub struct SinsemillaConfig {
     pub(super) lookup_config_4: LookupRangeCheckConfig<pallas::Base, { sinsemilla::K }>,
 }
 
-impl SinsemillaConfig {
-    pub fn advices(&self) -> [Column<Advice>; 5] {
-        [self.bits, self.lambda_1, self.lambda_2, self.x_a, self.x_p]
-    }
-}
-
 #[derive(Eq, PartialEq, Clone, Debug)]
 pub struct SinsemillaChip {
     config: SinsemillaConfig,